Rigid, stretchable and full recyclable cellulose reinforced thermoset elastomer composites for photothermal conversion and Joule heating

The utilization of biomass resource to fabricate multi-functional thermoset elastomer with full recyclability and high stretchability is desirable but remains challenging. Herein, a cellulose reinforced thermoset elastomer with excellent recyclability and stretchability is designed to address this challenge. To fabricate the thermoset elas-tomer, the cellulose macro-crosslinker bearing maleimide group was utilized to react with the furan modifying poly(styrene-block-butadiene-block-styrene) (SBS) through thermally reversible Diels-Alder (DA) reaction to construct the dynamic crosslinked thermoset elastomer. The formation of dynamic crosslinked network was demonstrated by stress relaxation, swelling, and DMA tests. Importantly, the formation of the dynamic cross -linking network not only improved the mechanical property, but also endowed the thermoset elastomer with thermal recyclability and solid-state plasticity, and the recycling efficiency was 88.1 %. Furthermore, the recyclable thermoset elastomer composite doping with CNT showed excellent and reliable photothermal con-version and Joule heating performance, and the surface temperature of the composite film rapidly reached 126.3 degrees C under the voltage of 7.5 V by Joule heating. These thermoset elastomer composites showed promising applications in the fields of photoelectric generators and rapid deicing coating.